Researchers at the University of Hamburg have developed an experimental memory storage technology that could replace the hard drives of today’s computers.
Guido Meier at the University of Hamburg in Germany and colleagues used nanosecond pulses of electric current to push magnetic regions along a wire at 110 metres per second – a hundred times faster than was previously possible.
In his device, a U-shaped magnetic nanowire is embedded into a silicon chip. Magnetic domains are then moved along the wire by pulses of polarised current, and are read by fixed sensors arranged in the silicon itself.
By switching powerful magnetic fields on and off, the researchers were able to rapidly create magnetic domains in a wire less than a micron wide made of permalloy – a magnetic material made of iron and nickel that is often found in disk drives.
These regions contains many magnetic atoms all aligned in the same direction and are separated by domain walls – thin regions where the atoms change their magnetic orientation from one alignment to the other. These can then be moved using much shorter nanoscale pulses.
A powerful x-ray microscope, capable of resolving features as small as 15 nanometres, was then used to read this information by snapping images of domain walls before and after the nanosecond current pulses. Future hard drives could store data by designating a domain wall to be a binary one, while its absence could be interpreted as a binary zero, the researchers say.
I know that it seems like every so often the death knell the hard drive is sounded: bubble memory, solid state disks, etc. What was interesting to me is that this reminded me of the description of rope core memory that was used for the Apollo Guidance Computer (AGC) from the Moon Shots.
The AGC used a unique form of Read Only Memory (ROM) known as “rope core memory” to store its operating program. This technology was a derivative of magnetic core memory but worked in a slightly different way: rather than magnetizing individual cores clockwise or counter-clockwise in order to store a 1 or a 0, rope core memory treated each core as a transformer core within a matrix of discrete wires. Wires running through the core stored a 1, those bypassing the core represented a 0.
This just goes to show that all the really good ideas never really die. Hmmm… just in time for the next round of Moon Shots. That is if you believe we really landed on the Moon.